java - Android 中的 Log.e

Question

我正在尝试登录我的程序，以便它帮助我进行调试，但 Log 语句本身给出了一个错误。日志信息我是这样写的

import android.util.Log;
public static final String TAG = "MyActivity";
Log.e(TAG,"I shouldn't be here");

这是我在公开课上发表的声明。它给出了错误:

1. Syntax error on token "(", delete this token.
2. Syntax error on token, Variable Declarator Expected instead.

我是 Android SDK 开发和 Java 的新手，因此我们将不胜感激。

谢谢。

我在这里输入我的确切代码:

package com.android.record;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import android.app.Activity;
import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.widget.Button;
import android.util.Log;
//import com.android.record.R;


public class AudioRecordTest extends Activity {
private static final int RECORDER_SAMPLERATE = 8000;

private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;

private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;

private AudioRecord recorder = null;
 private Thread recordingThread = null;
 private boolean isRecording = false;
 public static final String TAG = "MyActivity";

 @Override
 Log.e(TAG,"I shouldn't be here");  
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);

  setContentView(R.layout.activity_audio_record_test);

  setButtonHandlers();
  enableButtons(false);

  int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,
    RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);
 }

 private void setButtonHandlers() {
  ((Button) findViewById(R.id.btnStart)).setOnClickListener(btnClick);
  ((Button) findViewById(R.id.btnStop)).setOnClickListener(btnClick);
 }

 private void enableButton(int id, boolean isEnable) {
  ((Button) findViewById(id)).setEnabled(isEnable);
 }

 private void enableButtons(boolean isRecording) {
  enableButton(R.id.btnStart, !isRecording);
  enableButton(R.id.btnStop, isRecording);
 }

 int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we use only 1024
 int BytesPerElement = 2; // 2 bytes in 16bit format

 private void startRecording() {

  recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
    RECORDER_SAMPLERATE, RECORDER_CHANNELS,
    RECORDER_AUDIO_ENCODING, BufferElements2Rec * BytesPerElement);

  recorder.startRecording();

  isRecording = true;

  recordingThread = new Thread(new Runnable() {

   public void run() {

    writeAudioDataToFile();

   }
  }, "AudioRecorder Thread");
  recordingThread.start();
 }

        //Conversion of short to byte
 private byte[] short2byte(short[] sData) {
  int shortArrsize = sData.length;
  byte[] bytes = new byte[shortArrsize * 2];

  for (int i = 0; i < shortArrsize; i++) {
   bytes[i * 2] = (byte) (sData[i] & 0x00FF);
   bytes[(i * 2) + 1] = (byte) (sData[i] >> 8);
   sData[i] = 0;
  }
  return bytes;
 }

 private void writeAudioDataToFile() {
  // Write the output audio in byte
  String filePath = "/sdcard/MyApp/8k16bitMono.pcm";

                short sData[] = new short[BufferElements2Rec];

  FileOutputStream os = null;
  try {
   os = new FileOutputStream(filePath);
  } catch (FileNotFoundException e) {
   e.printStackTrace();
  }

  while (isRecording) {
   // gets the voice output from microphone to byte format
   recorder.read(sData, 0, BufferElements2Rec);
   System.out.println("Short writing to file" + sData.toString());
   try {
    // writes the data to file from buffer stores the voice buffer
    byte bData[] = short2byte(sData);
    Log.v(TAG,"Am I here??");                // Here is my log!!
    os.write(bData, 0, BufferElements2Rec * BytesPerElement);

   } catch (IOException e) {
    e.printStackTrace();
   }
  }

  try {
   os.close();
  } catch (IOException e) {
   e.printStackTrace();
  }
 }

 private void stopRecording() {
  // stops the recording activity
  if (null != recorder) {
   isRecording = false; 
   recorder.stop();
   recorder.release();

   recorder = null;
   recordingThread = null;
  }
 }

 private View.OnClickListener btnClick = new View.OnClickListener() {
  public void onClick(View v) {

   switch (v.getId()) {
   case R.id.btnStart: {
    enableButtons(true);
    startRecording();
    break;
   }
   case R.id.btnStop: {
    enableButtons(false);
    stopRecording();
    break;
   }
   }
  }
 };

        // onClick of backbutton finishes the activity.
 @Override
 public boolean onKeyDown(int keyCode, KeyEvent event) {
  if (keyCode == KeyEvent.KEYCODE_BACK) {
   finish();
  }
  return super.onKeyDown(keyCode, event);
 }
}

Answer 1

@Override
Log.e(TAG,"I shouldn't be here");  
public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);

Log.e() 等方法调用应该在方法体中。它们不能直接在类主体中。所以，把它改成这样:

@Override
public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  Log.e(TAG,"I shouldn't be here");